Marine bulk-cargo unloading boom



Feb. 2,, 1943.

c. M. RUDOW MARINE BULK-CARGO UNLOADING BOOM Filed Jan. 5, 1959 aSheets-Sheet 1 Feb. 2, 1943. c. M. RUDOW MAINE BULK-CARGO UNLOADING BOOMFiled Jan. 3, 1939 3 Sheets-Sheet 2 Feb. 2, 1943. QM; RUDOW MARINEBULK-CARGO UNLOADING BOOM Filed Jan. 5. 1939 3Sheets-Sheet 3 Eg PatentedFeb. 2, 1943 I means 5 cranes. (o1 214-44) This invention relates tobulli-cargo unloaders for ships and other vessels, and particularly toboom-conveyors used for ischargi ng cargo from a ship to a pointbeyond:the sides thereof or for shifting the location of bulk c'arg'o within aship.

Such devices heretofore used comprised a trussed boom carrying a beltconveyor of fixed length, the boom being pivotally supported at one endand generally on the longitudinal axis of the ship or vessel, andarranged for vertical angular motion about the 'pivot provided by any ofseveral well known means, usually a system of hoisting tackle extendingfrom some point on the boom to an A-frame centering over the pivotsupport and thence to driven drums located at any convenient place. Suchbooms are also arranged for horizontal angular motion usually providedby swing tackle hitched to the boom and the deck of the ship, thuspermitting the boom to be inclined to substantially any vertical angleand swung to any horizontal angle within clearance limitations on theship and in accordance with the conditions at a given unloading site.

The length of 'such booms and conveyors is, however, limited and fixed,thus limiting the locus of discharge or unloading points, and at timesnecessitating awkward handling or docking or the vessel, which is notalways convenient and often requires long delays before docking space ofsuitable size is available.

The main objects of this invention are to provide structural andeconomical improvements in bulk cargo unloading boom conveyors for lake,river or ocean vessels; to provide an improved arrangement of boomelevating tackle whereby weight and cost of boom, tackle and A-frame canbe reduced; to provide a device for increasing the operating length of aboom conveyor beyond its stowed length by varying amounts readily and atwill; and to provide a device for reducing the operating length of aboom conve or below its stowed length by varying amounts readily and atwill.

Other objects of the invention are to provide a device permitting thebuilding of a higher pile of material at a given shore site than wouldbe possible otherwise; to provide a device permitting the deposit ofmaterial on shore at points without changing the position of the vessel;to

provide'suc'h a.- d'e'vioe permitting a vessel greatly increasedlatitude in utilizing anchorages that would otherwise be unfavorableorimpossible, and to provide" an unloading device which, in permitting thegradual building up of piles to increased heights without movement ofthe vessel minimizes the degradation of cargo due" to breakage:

Further objects of the invention are to provide an improved unloadingdevice which makes the boom unloader principle valuable to small vesselsor vessels of limited clear deck space for which it would otherwise havelittle or no economic value; to provide such a device whichco'rre'spond-- in'g enhances the value of the boom urfloader principleon vessels having greater clear deck space; and to provide such a devicewhich redudes difircu'lties and hazards incidental to the necessity ofswinging the boom outward while taking on cargo; namely, the possibledelays and the certain legal'risks arising from the obstructi'oii oftr'afiio and the labor and expense of oor rooting l'i'stof the vessel soinduced;

g A sse'eifie embodiment of the inventionlis shown in the accompanyingdrawings in which: Figure 1 is side elevation of a ship embodying animproved uhloa'der boom.

Fig. 2 is a view showing a vessel in end elevation with the improvedunloader boom in extended position to illusftr ate the range of"bulkcargo discharging points beyond the side of the vessel. a I,

Fig. 3 is a detailed view showingthe outboard end of thefixed portion ofthe boom and the arrangement of a shuttle extension therefor.

Fig. 4 is a view in elevation showing the arrangement of the inboard endof the main boom.

Figs. 5 and 6 are diagrammatic illustrations in plan showing one mannerof operating the boom extension.

Fig. 7 is a sectional view in vertical elevation of the fixed boom andshuttle, showing their mechanical arrangement and inter-relation.

- Fig. 8 is a fragmentary view in side elevation showing the'manner ofsupporting the inboard end of the shuttle boom when the same is inretracted position.

Fig. 9 is a fragmentary sectional view as taken on line 9-9 of Fig. 8. r

Fig. 10 is a sectional view in elevation showing the arrangement of theinboard end support of the main boom for both vertical andhorizontalpivotal movement; and,

Fig. 11 is a fragmentary sectional view of the main boom and shuttleshowing the arrangement of lateral guide wheels on the shuttle.

As shown in the drawings, my invention makes use of a main conveyor boomof such length as can be stowed on a ship deck in the usual manher, theconveyor carried by the boom being of a continuous belt type in thearrangement shown. A shuttle extension boom is carried by the main boomand, as shown, telescopes within the same, running on tracksincorporated within the structures and being actuated by means of cablesor other appropriate means whereby the shuttle may be run out to andheld at the desired length within limits, as determined by the length ofthe main boom.

The shuttle, as shown, carries a second belt conveyor arranged below theconveyor on the main boom; the latter, receiving its load in any of theusual manners, discharges the load over its head or outward end onto theshuttle conveyor, which, in turn, carries the load over the extendeddistance and discharges it to the shore.

The direction of travel of the shuttle conveyor is reversible; thus,from a given anchorage, the shuttle not only extends the unloadingradius through all parts of a zone determined by its own working lengthbeyond the working radius of the main boom, but also permits unloadingthrough substantially all parts of the zone within the radius of themain boom.

Referring specifically to the drawings, a typical illustration is shownin Fig. 1, wherein the main boom I is shown in stowed position, the mainboom taking up all the available clear length of the vessel deck andbeing supported at one end by a pivot support 2 mounted on a horizontalturntable on the deck of the ship 3, and at the opposite end by asupporting means 4, which helps to carry the weight of the boom when thehoisting tackle 5 is not in use.

As shown in Fig. 1, cable 6 of the hoisting tackle runs to suitablesheaves on an A-frame I, and thence to a hoisting drum 8 driven by anysuitable means such as an electric or gasoline motor, and the outer orremote end of the tackle is attached at 9 to the lower chord of the mainboom truss structure adjacent to its outer end. This arrangement of thehoisting tackle is an important feature of my invention.

In the conventional design the hoisting tackle is attached to some pointas at I II, on the top chord of the main boom I, necessarily at an acuteangle with it, and the acuteness of this angle necessitates a heavytension in the tackle and a correspondingly heavy compression in the topchord of the boom in order to carry the boom weight. The top chordcompression must in such case. follow an indirect path to the reactionpoint, which is the pivot 2, located below the line of the top chord andquite close to the bottom chord.

Thus in such conventional design the top chord compression or thebalancing force between the weight supported and the tackle tension infollowing this indirect path to the reaction point sets up stresses inthe truss framing for which the latter need not otherwise be designed.These stresses in the truss framing will generally be of opposite signor character to those otherwise obtaining and of many times greatermagnitude. The result is the necessity of a considerable increase intruss weight which my design makes unnecessary, this extra weight beinghigh above the center of gravity of the vessel at an elevation whereelimination of weight is of great Value in conserving stability.

By connecting the tackle to a point on the lower chord, as in myimproved design, the compressive stress on the boom is transmitted quitedirectly along the bottom chord to the pivot and this permits thelighter construction of the boom without sacrifice of strength.

As shown in the drawings and particularly in Figs. 2, 3, 4, and 7thereof, my improved unloading boom construction is generallyrectangular in cross section and comprises a hollow frame made up ofspaced parallel elongated vertically disposed trusses, within which agenerally U-shaped shuttle boom I I is telescopingly housed, the shuttleboom likewise being of hollow rectangular trussed frame construction.

As shown, the main boom I also carries an endless belt conveyor I 2supported on suitably spaced hangars I3, as shown in Fig. 7. Theconveyor I2 is of fixed length and runs from adjacent to one end of themain boom I to the opposite end, passing over suitable pulleys I4 and I5at the inboard and outboardends of the main boom re spectively and alsopassing over suitable spaced supporting or idler rollers I6 and II, thewhole being supported on framework carried by hangers I3.

As shown in Figs. 1, 2 and 4, the main boom conveyor I2 is driven by asuitable motor, or other power medium, and gearing I8 usually located atthe inboard end of the main boom. A suitable loading chute 2!] isprovided at the inboard end of the main boom conveyor I2 in the usualmanner to properly guide the material being handled onto the same, and asuitable discharge chute ZI is provided at the opposite end of the mainboom to guide the conveyed material onto the conveyor ofthe shuttle boomI I, as will be hereafter described. Thus, material taken from'the holdof the ship by any suitable means,

such as an elevator 22, is delivered onto the conveyor I2, carried thelength of the main boom I, and deposited onto the conveyor 23 of theshuttle I I.

As shown in Figs. 3 and 7, the shuttle boom II, which in the form showntelescopes into the main boom I, carries a conveyor 23 which extendsover substantially its whole length and is supported-on tail pulley 2head pulley 25, snub pulley 24A, bend pulley 251 and suitable spacedintermediate idlers 26 and 21, the several pulleys and idlers beingsuitably mounted on the shuttle framing. Also as shown, this conveyor isdriven by a suitable motor or other power means I9. located near theinboard or tail end of the shuttle andhaving driving connections withthe tail pulley 24.

As before mentioned, the drive for the shuttle boom conveyor 23 isreversible so that the conveyor may travel in either direction to carrymaterial delivered onto the same either toward the inboard or theoutboard end of the shuttle boom. Thus, with the conveyor I2 of the mainboom extending along the upper part thereof above the shuttle boom II,material may be delivered onto the shuttle boom'conveyor 23 regardlessof the position of the shuttle boom with respect to the outboard end ofthe main boom I, and wholly independently of the direction of travel ofthe shuttle boom conveyor.

It will be seen that with this arrangement the shuttle boom Will serveeither as a means for transporting the conveyed material to a pointbeyond the outboard end of the fixed or main boom or to carry theconveyed material backwards from the outboard end of the main boom tosubstantially any point intermediate the ends thereof, thus providingdelivery to any point within an arcuate zone extending from the side ofthe ship to a distance substantially equiva' lent to the sum of thelengths of the main boom -I and the shuttle I I and making the actual'de livery or discharge point independent of the length of the mainboom.

Another important advantage gained by my improved conveyor boomarrangement is that cargo may be taken from one part of the 'ships holdand deposited in another part in a single operation, thus obviating thenecessity, as in the usual case, of fil'Sl/ discharging the cargo to theshore and then reloading the same.

As shown in the drawings, the shuttle boom II together with its conveyoris advanced or retracted by movement of the shutie boom along the axisor" the main boom, the shuttle boom being so constructed run over aplurality of guide wheels on which i is supported for t'ele scopingmovement relative to the main boom. As shown in Figs. and upper andlower guide wheels 23 and 29. respectively. are supported on the mainboom structure adjacent the outer end of the same, a of upper guidewheels 28 and a pair of lower 11 wheels 2% being located, at or near theouter end of the main boom, and pairs of upper and lower guide wheels28.3 and 29A respectively being located inwardly of the end of the mainboom at or near the point of farthest outward travel of the inner end ofthe shuttle boom. Thus in any extreme operating position the weight ofthe shuttle is carried by one pair of lower guide Wheels acting as afulcrum against the reaction of the remote pair of upper guide wheels.In any intermediate position in which center of weight lies between theinner and outer pairs of wheels the shuttle is carried by two pairs oflower wheels.

As shown, the guide wheels 28, 231, and 29.! are flanged and arranged toengage tracks 30 and 3| extending along the upper and, lower chords ofthe shuttle trusses. Thus the shuttle is stably supported in all workingpositions, the guide wheels being mounted on shafts, not shown,journalled in suitable bearings 82, fixedly mounted on the main boomstructure.

In order to provide lateral stability fixed side guide rollers 33located at or near the outer end of the main boom and arranged to engagetracks 34 on the upper end lower chords of the shuttle boom' trusses areprovided, and moving guide rollers 35 are mounted on the shuttle at ornear the inner end thereof as shown in Fig. 11, the guide rollers 35travelling with the shuttle I I and contacting tracks 35 suitablypositioned and extending along the trusses of the main boom I. Theseguide rollers assure freedom from jammine; in changing of the length ofthe unloader boom and serve to carry wind and other lateral loads fromthe lateral bracing system of the shutthe truss to that of the mainboom.

Since shuttle motion in either direction and control of the same must bepossible at any vertical inclination which might be used, a cable systemof fixed length for actuating the shuttle boom is provided. As shown inthe drawings, with particular reference to Figs. and 6, this cablesystem comprises a sheave 3i fixed to the main boom at a point near theouter end thereof on the bottom lateral truss system and arranged so asto be aligned with the longitudinal center line of the shuttle; a cable38 having a fixed attachment to the inner end of the shuttle and passingaround the sheave 31; and a winding drum 39 around which the cable 38 iswra ped, mounted at the inner end of the main boom. The cable -38 makesseveral turns around the drum 39 and then runs back to the inner end ofthe shuttle boom I I. At this point both ends of the cable are attachedto the shuttle boom.

As indicated in the drawings, the winding drum 39 may be driven ineither rotative direction by any suitable motive power such as anelectric motor ii] operating through speed reduction gearing '4 I. Aswill be readily understood, the diameter and grooving of the drum 39mustbe proper for the cable used and the length of the drum must besufficient for the number of turns of the cable, which would equate inlength to the maximum distance of shuttle travel plus at least fouradditional turns for friction anchorage. Thus the cable being endless,the anchorage turns travel back and forth the length of the drumaccording to the shuttle movement. Itwill also be understood that theshuttle operating mechanism includes besides the motor 40 and speedreduction gearing 4| suitable brake and clutch mechanism notspecifically shown, as half of the shuttle operation will consist ofbrake action against closing of the shuttle by gravity when the mainboom is in upwardly inclined position.

It will be seen that when the shuttle is in retracted position most ofits length becomes a cantilever supported on the relatively shortanchorspan between the outer and inner sets of guide wheels 28 and 29.1 on themain boom and since it is undesirable to subject such a long cantileverto the abuse which it would receive from motion of the ship while theshuttle is in stowed position, means are provided adjacent to the innerend of the main boom to anchor the inner end of the shuttle when thesame is in stowed position. Such means are illustrated in Figs. 8 and 9of the drawings and as shown, comprise a straight-faced wheel or'tailguide 42 mounted on the bottom chord of each of the shuttle trusses andguideways or runways 43 mounted on supports in the plane of the bottomchord of the main boom in alignment with the tail guides 42.

As shown, theguideways 53 are inclined upwardly in the rearwarddirection so that as the inner end of the shuttle approaches the stowedposition the tail guides 42 Will contact the guideway 43 and elevate theinner end of the shuttle a sulficient amount to take up the computedelastic dead load deformation of the cantilever when the end of inwardtravel of the same is reached. Preferably the vertical inclination ofthe guideway 43 is slightly in excess of the computed cantileverdeformation to assure easy making and breaking of contact with the tailguide 42. Also the side guides 14 of the guideways 43 are flaredoutwardly in the forward direction of the main boom to insure easy entryof the tail guide onto the runway under all conditions of lateraldistortion of the shuttle. At the end of shuttle travel, however, thespace between the side guides M is narrowed to working clearance of thetail guide, thus providing a lateral anchorage which will be firm whilethe vessel is in motion. Wheel stops 45 are also provided to preventover travel of the shuttle in the closing or retracting movement of thesame and it will be understood that suitable known means will beprovided for automatically shutting off the motor drive of the shuttleoperating mechanism when the tail guide wheels 42 contact the stops 45or when they pass some predetermined point short thereof. Also suitablelocking means, such as the wheel locks 46, may be provided which willoperate automatically to hold the shuttle in the retracted position; andsuitable means, either manually or automatically operated, or both, maybe provided for opening or removing the locking means when it is desiredto extend the shuttle.

As shown, in Fig. 10, the pivot support 2 for the inboard end of themain boom I comprises a turntable 41 pivotally mounted on the verticalaxis of a base plate 43, suitable roller bearings being disposed betweenthe turntable and the base plate. Also, as shown, the turntable 41 isprovided with opposed laterally-projecting trunnions 56 on whichsuitable supporting bearings 5! attached to the inner end of the mainboom are journalled. This construction is well known and provides ampleefficient support for the main boom under all conditions of horizontalor vertical angular movement of the same.

In the operation of my improved unloader boom the device is elevated tothe desired vertical angular position by means of the hoisting tackle 5running from the A-frame I centering over the pivoted or supported endof the boom; and lateral angular motion of the boom is effected by meansof suitable swing tackle, not shown, but of established conventionaldesign. When the main boom has been swung to its desired position andvertical angle, the shuttle is then run out or extended to the desiredamount by means of the shuttle drive 434l and the endless cable and drum38 and 39, respectively. The main boom conveyor !2 and the shuttle boomconveyor 23 are then actuated by their respective drives which arearranged for remote control. The bulk-cargo of the vessel is then takenfrom the hold by any suitable cargo-handling means and deposited on themain boom conveyor 12 through the chute 20. The cargo is then carried tothe chute 2| where it is delivered onto the shuttle conveyor 23, whichin turn, discharges the cargo to a shore pile.

When the shore pile location is beyond the end of the main boom,-as at Ain Fig. 2, the shuttle boom conveyor will travel in the outwarddirection and discharge, the cargo over the outward end of the shuttleboom. When the shore pile is desired to be located at a point betweenthe end of the main boom and the ship, as at B in Fig. 2, the shuttleconveyor is run in the reverse or rearward direction so as to dischargethe cargo over the rearward or innermost end of the shuttle. It willthus be seen that latitude as to location, size and shaping of piles ofcargo as deposited on the shore by this device is much greater thanwould be possible with unloader booms of conventional design, in whichunloading is confined to a single fixed and relatively short radius.

It is to be understood that though the conveyors herein shown anddescribed are of the continuous belt type my invention is not to beconstrued as being limited thereto; and that any suitable kind or typeof conveyor may be employed.

The chief advantage of my invention is the increment of working reachover that possible with an unloader boom of fixed length subject to thesame limitation of stowed space. A second advantage is the facility forvarying the Working reach throughout substantially the whole length ofthe elongated boom.

The usefulness of these advantages can be illustrated by considering theexample of a vessel having a clear deck space to stow a boom 100 feetlong. Without my invention such a boom would carry a conveyor about 100feet long. Bulk commodities can be carried by such a conveyor upinclines of 15 to 25, the angle depending upon the material carried.Thus, assuming an 18 incline, this conveyor will deposit a maximum pile3| feet high measured from the top of the delivery pulley of theconveyor, or about feet high measured from the deck of the vessel, on afixed radius of 95 feet from the center of horizontal rotation usuallyon the center line of the vessel.

For the same 100 feet stowed length my invention would afford operatinglengths variable at will from a maximum of about 1'70 feet to a minimumof about 30 feet. Under the same operating conditions my improvedconveyor boom would deposit a maximum pile about 56 feet higher than thedeck of the vessel on a radius of approximately 161 feet from the axisof horizontal rotation. It would also deposit a pile on any lesserradius down to the 30 foot minimum, the height of the pile varying withthe radius.

With such an advantage a vessel can discharge cargo over a greatlyincreased land area and to a greatly increased average depth. Inaddition to this increase in the use of shore space my invention alsopermits increased freedom and convenience of handling. Thus a ship ofdeep draft can discharge a cargo from a more remote anchorage if waterat the dock line is too shallow or it can on occasion discharge cargowithout Waiting for another ship to vacate the berth which it would haveto use without such equipment.

My invention also offers a number of advantages in the use of shorestorage. A storage site otherwise valueless may be made usable by theincreased reach of the boom conveyor extension and the capacity of anyestablished cargo site is greatly increased. Cargoes can also bedisposed adjacent to service roads or railroad spurs more advantageouslywithout additional cost and the ability to discharge different materialsto separate piles without reberthing the ship is increased severalhundred per cent.

The dealer in commodities so handled profits, in addition to such gainsas the foregoing may ultimately give him, in the improved condition inwhich the material reaches him. The high lift afforded by the extensionresults in the building up of fewer and larger piles. Further, there isless casual loss from such piles, less risk of mixture with foreignmatter and the building up of the piles is considerably slower. Also,the average distance of drop from the conveyor to the pile will, inordinary practice, he reduced with a consequently reduced degradationthrough breakage of sized material.

Aside from these advantages the useful scope of the unloader boomprinciple is made possible to many vessels on which it would otherwisehave little or no economic value. A vessel having clear deck space toolimited, either because of its size or the presence of deck structures,cannot profitably use the fixed length conveyor boom which itsclearances permit. It can, however, in many instances so use anextensible boom. Where limitations are less sharp the device stilloffers great advantages. For any available deck space a relativeenhancement of Value over that of a fixed length boom can be provided,the only final limitation being the stability of the boat. In the addsthe advantages of the variable radius of dis-- charge to equal maximumrange. Also the economy of stowed length with my improved constructionaffords wide latitude in locating the inboard support at such a point aswill give the most desirable arcs of horizontal swing together with themost convenient working of the vessel.

When loading the vessel it is necessary to extend the boom outboard atapproximately right angles, and always on the oil-shore side, to gainaccess to hatchways. The compactness of my invention as compared with aboom of fixed equal operating length minimizes the list of the vessel soinduced and the difiiculties and hazards incidental to obstruction ofpassing trafiic.

Furthermore when it becomes necessary to shift cargo from one portion ofthe vessel to another with the fixed length boom conveyor the materialmust first be unloaded to the shore and then reshipped by means of shoreequipment. Whereas with my improved device the cargo may be shiftedwithout taking it off the vessel and without any equipment other thanthat used in the ordinary discharge of cargo.

Although but one specific embodiment of this invention is herein shownand described, it will be understood that details of the constructionshown may be altered or omitted without departing from the spirit ofthis invention as defined by the following claims.

I claim:

1. A cargo unloading device comprising a main boom, a shuttle boommovable along said main boom for variable longitudinal extensionthereof, means adjacent the outward end of said main boom arranged tosupport said shuttle boom independently in all positions of movement ofthe same, a tail guide on the inward end of said shuttle boom, and tailguide receiving means in appropriate position on said main boom toengagingly receive said tail guide automatically and secure the inwardend of said shuttle boom against displacement when the same is inretracted position.

2. In a cargo unloader comprising a hollow main boom having alongitudinally-disposed shuttle boom therein arranged to betelescopingly extended therefrom and retracted thereinto, said shuttleboom being movably carried by and mainly supported between spaced upperand lower pairs of guide means disposed adjacent the outward end of saidmain boom, a tail guide on the inner end of said shuttle boom, andforwardly-flared longitudinally-extending means on said main boomarranged to receive said tail guide when said shuttle boom is retractedand secure the inward end of said shuttle boom against displacement whenthe same is in stowed position.

3. In a ship-board cargo unloading device comprising an extensible boompivotally supported on a boat from a fixed point at one end for bothvertical and horizontal angular movement and having side frames each ofwhich is a vertically-disposed truss extending the length of the boom,the said pivot connection attaching to the lower chords of said trusses,elevating tackle extending from a point adjacent the pivotally-supportedend of the boom and above the point of boom support and attached to thelower chord of each of said side frame trusses adjacent the middle ofthe maximum operating length of said boom.

4. In a boat unloader comprising a boom and cargo conveyor of specificlength, said boom having one end pivotally connected to the boatstructure, means including a second conveyor operable independently ofthe first conveyor and adjustable longitudinally thereof to vary thepoint of ultimate cargo discharge axially of said boom either axialdirection with respect to the outward end thereof, said boom beingarranged for both vertical and horizontal pivotal movement relative tothe boat, and said means and second conveyor being mounted and arrangedfor operation irrespective of the attitude of said boom relative to saidboat and the pivot connection thereon.

5. The combination with a boat of an unloading boom of fixed lengthhaving one end pivotally secured to the boat and having a longitudinallyextending conveyor discharging adjacent its outward end, a shuttle boomcarried parallelly by and wholly supported by the first boom andarranged to be adjustably extended beyond the outward end thereof, areversible longitudinally extending conveyor on said shuttle boomarranged to receive material discharged from the first conveyor and todeliver said material from either end irrespective of the position ofsaid shuttle boom with respect to the outward end of the first boom, andmeans to swing said first boom horizontally on its pivot and project thesame outwardly beyond either side of said boat, all arranged wherebymaterial may be discharged from said shuttle to any point between theside of the said boat and the farthest extended reach of said shuttle.

CHARLES M. RUDOW.

